Is there a battery for my new Sprint 8830 World Edition that lasts longer than the one that comes with it? Is there a charger that will charge the battery by itself or, as I've had with my Treo, a charger that takes one battery and one phone and charges them both at the same time?

Try some of these links:

1600MAH OEM SIZED EXTENDED LIFE BATTERY FOR BLACKBERRY 8800/8820/8830 - BASI16BBX2S

OEM BlackBerry 8830 Power Station with Extra Battery Charger